I wouldn't throw it away just yet. Play it for a while. Give it time to blossom and show you what the game is really about. Try to notice the things that make the game different from all the other shooters out in the world.
Then, when you finally do return to your other games, you'll be able to more fully appreciate them after experiencing the disappointment and decline of the Duke.
...
Nah, who am I kidding? Don't bother.